<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <form action="./文件上传.php" method="post" enctype="multipart/form-data">
         <!-- <input type="hidden" name="MAX_FILE_SIZE" value="2"> -->
         <input type="file" name="image">
         <input type="submit" value="上传" name="sub">
    </form>
</body>
</html>

<?php
 if(!empty($_POST)){
     if($_FILES['image']['error']==0){
         move_uploaded_file($_FILES['image']['tmp_name'],'./upload'.$_FILES['image']['name']);
     }else{
         echo "上传失败"+$_FILES['image']['error'];
     }
 }
?>